As someone who has grown in pots for decades, there really is no way to make a soil suitable for an entire cycle.
You will have to give supplemental feeding sooner or later.
A nice rich mix designed to last will be too strong for seedlings and a milder mix will not provide enough nutrition for flowering.
The best compromise is a mix that will be ok for life until the beginning of flowering, but you will need to fertlize from early/mid flowering onwards.
A mix that will carry right through the flowering cycle will burn/kill seedlings, ............so, water only is not really achievable in my experience.